Mechanical Properties of Lead Free Solder Alloy Measured by Nanoindentation

The elimination of lead from electronics due to its detrimental effects to environment is pushing component manufacturers to consider lead free solder alloy as an option. Application of lead free solder alloy requires a better understanding of its mechanical behavior at elevated temperatures and at small volume size. Such information is still lacking. In this study, nanoindentation technique was used to investigate the deformation behavior of the near eutectic ternary SAC387 (Sn 95.5 wt%, Ag 3.8 wt% and Cu 0.7 wt%) lead free solder alloy. The mechanical properties of each constituent phase in SAC387 were carefully measured and analyzed. Indentation tests were performed with different holding times to study the creep effects on the mechanical properties measured by nanoindentation. Microhardness tests were also carried out at temperatures above ambient temperature to investigate its influence on the mechanical properties.